Research was carried out on motor function in man in relation to aging and disease. With the use of a patient activity monitor worn on the non-dominant wrist in 14 healthy men for a period of 10 days, it was demonstrated that average wrist motor activity was lower in older individuals, primarily as a result of low activity during daytime hours. Sleep duration could be estimated from the analysis, and was not correlated with age. A quantitative neurological examination was standardized in healthy men between 20 and 80 years of age, and established curves for age related declines in coordination, speed and accuracy of movement. There was significant correlation between age and peripheral hearing sensitivity in healthy men, particularly at high frequencies, but when the effects of hearing loss due to age were taken into account, measures of speech discrimination and tympanomemetry were not related significantly with age. An outpatient Dementia Clinic was initiated at the Clinical Center in Bethesda, to screen subjects for entry into inpatient protocols and for developing instruments for the differential diagnosis and determination of progress of Alzheimer's disease.